The Director General of MI5 also explained how extremists can exploit ‘safe spaces’ online, and issued a fresh challenge to tech firms by saying they have an ‘ethical responsibility’ to help the government confront the threat.

Advertisement

Advertisement

These are the first substantial remarks made by Parker since Britain was hit by a flurry of terror attacks this year.

Security forces have foiled 20 plots in the last four years, including an astonishing seven in the last seven months.

The UK has suffered a flurry of terror attacks this year (Picture: REX/Shutterstock)

‘We’ve seen a dramatic up-shift in threat this year,’ Parker said in a speech delivered in central London. ‘Today there is more terrorist activity, it’s coming at us more quickly, and it can be harder to detect.’

Police and security services are now operating at a scale which Parker said is ‘greater than every before’, with well over 500 live operations involving around 3,000 individuals.

‘Extremists of all ages, gender and backgrounds united only by the toxic ideology of violent hatred that drives them,’ he said.

‘These threats are sometimes now coming at us more quickly – whether crude but lethal attack methods, for example using a knife or a vehicle, or more sophisticated plots, when in today’s world terrorists can learn all that they need online to make explosives and build a bomb.’

Police have foiled seven attacks in the last seven months (Picture: AFP/Getty Images)

Parker said that attacks can sometimes accelerate ‘from inception through planning to action in just a handful of days’, adding: ‘This pace, together with the way extremists can exploit safe spaces online, can make threats harder to detect and give us a smaller window to intervene.’

And while Isis is ‘rapidly losing ground’ in its heartlands in Iraq and Syria – having just lost its de-facto capital Raqqa – tackling the ideology itself will require ‘sustained international focus for years to come’.

Advertisement

Advertisement

But he did say that the vast majority are being found and stopped, and that their response to the threat would be ‘unrelenting’.

‘Those that wish our country harm can expect to meet MI5 and the police,’ he said defiantly. ‘They will face the full force of the law and be brought to justice.’